es6-arrow-function 

Compiles JavaScript written using arrow functions to use ES5-compatible
function syntax. For example, this:

``js
[1, 2, 3].map(n => n * 2);
`

compiles to this:

`js
[1, 2, 3].map(function(n) { return n * 2; });
`

For more information about the proposed syntax, see the TC39 wiki page on
arrow functions.

Install

`
$ npm install es6-arrow-function
`

Usage

`js
$ node
> var compile = require('es6-arrow-function').compile;
[Function]
`

Without arguments:

`js
> compile('$(() => main());').code;
'$(function() { return main(); });'
`

With a single argument:

`js
> compile('[1, 2, 3].map(n => n * 2);').code;
'[1, 2, 3].map(function(n) { return n * 2; });'
`

With multiple arguments:

`js
> compile('[1, 2, 3].map((n, i) => n * i);').code;
'[1, 2, 3].map(function(n, i) { return n * i; });'
`

It binds the current context:

`js
> compile('stream.on("data", d => this.data += d);').code;
'stream.on("data", (function(d) { return this.data += d; }).bind(this));'
`

Or work directly with the AST:

`js
$ cat ast.json
{
"type": "Program",
"body": [
{
"type": "ExpressionStatement",
"expression": {
"type": "CallExpression",
"callee": {
"type": "Identifier",
"name": "$"
},
"arguments": [
{
"type": "ArrowFunctionExpression",
"id": null,
"params": [],
"defaults": [],
"body": {
"type": "CallExpression",
"callee": {
"type": "Identifier",
"name": "main"
},
"arguments": []
},
"rest": null,
"generator": false,
"expression": true
}
]
}
}
]
}
$ node
> var transform = require('es6-arrow-function').transform;
[Function]
> console.log(JSON.stringify(transform(require('./ast.json')), null, 2));
{
"type": "Program",
"body": [
{
"type": "ExpressionStatement",
"expression": {
"type": "CallExpression",
"callee": {
"type": "Identifier",
"name": "$"
},
"arguments": [
{
"type": "FunctionExpression",
"id": null,
"params": [],
"defaults": [],
"body": {
"type": "BlockStatement",
"body": [
{
"type": "ReturnStatement",
"argument": {
"type": "CallExpression",
"callee": {
"type": "Identifier",
"name": "main"
},
"arguments": []
}
}
]
},
"rest": null,
"generator": false,
"expression": false
}
]
}
}
]
}
`

Command line

If installing via npm a command line tool will be available called es6-arrow-function.

`
$ echo "()=>123" | es6-arrow-function
(function () {
return 123;
});
`

`
$ es6-arrow-function $file
(function () {
return 123;
});
`

Browserify

Browserify support is built in.

`
$ npm install es6-arrow-function # install local dependency
$ browserify -t es6-arrow-function $file
// BOILERPLATE
(function () {
return 123;
});
`

Contributing

![Build Status](https://travis-ci.org/square/es6-arrow-function)

$3

First, install the development dependencies:

`
$ npm install
`

Then, try running the tests:

`
$ npm test
`

$3

1. Fork it
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature`)
5. Create new Pull Request

Any contributors to the master es6-arrow-function repository must sign the
[Individual Contributor License Agreement (CLA)][cla]. It's a short form that
covers our bases and makes sure you're eligible to contribute.

[cla]: https://spreadsheets.google.com/spreadsheet/viewform?formkey=dDViT2xzUHAwRkI3X3k5Z0lQM091OGc6MQ&ndplr=1

When you have a change you'd like to see in the master repository, send a pull
request. Before we merge
your request, we'll make sure you're in the list of people who have signed a
CLA.